Calling CreateDefaultSubobject from constructor of Pawn makes NotifyHit event stop firing

I am modifying Microsoft AirSim:

My only change is changing this constructor: https://github.com/Microsoft/AirSim/blob/master/Unreal/Plugins/AirSim/Source/Multirotor/FlyingPawn.cpp#L11 to

AFlyingPawn::AFlyingPawn()
{
	wrapper_.reset(new VehiclePawnWrapper());

	static ConstructorHelpers::FClassFinder<APIPCamera> pip_camera_class(TEXT("Blueprint'/AirSim/Blueprints/BP_PIPCamera'"));
	pip_camera_class_ = pip_camera_class.Succeeded() ? pip_camera_class.Class : nullptr;

	InternalCameraBase1 = CreateDefaultSubobject<USceneComponent>(TEXT("InternalCameraBase1"));
	InternalCameraBase1->SetRelativeLocation(FVector(36.0f, 0, 50.0f)); //center
	InternalCameraBase1->SetupAttachment(RootComponent);
}

The problem lies in the line that contains CreateDefaultSubobject. When I add this line, the NotifyHit event on line 24 stops being fired. I think there is something I don’t understand about how collisions are signaled? Anyone have some insight to share?